Method and apparatus for manufacturing metal sheets and strips



June 11, 1935. F. c. BIGGERT; JR

METHOD AND APPARATUS FOR MANUFACTURING METAL SHEETS AND STRIPS 5 Sheets- Sheet 1 Filed Dec. 13, 1953 WITNESSIES June 11, 1935. F. c. BIGGERT. JR

METHOD AND APPARATUS FOR MANUFACTURING METAL SHEETS AND STRIPS Filed D80. 15, 1933 5 Sheets-Sheet 2 INVENTOR R m x o o o o a; w lll\ s K 3w I N u w. 3" mfi m w i u n u m n n m m H MW WITNESSES June 11, 1935. F. c. BIGGERT, JR

METHOD AND APPARATUS FOR MANUFACTURING METAL SHEETS AND STRIPS Filed Dec. 13,-1933 1". &,

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F. C. BIGGERT, JR

Filed Dec. 13, 1953 METHOD AND APPARATUS FOR MANUFACTURING METAL SHEETS AND STRIPS June 11, 1935.

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METHOD AND APPARATUS FOR MANUFACTURING METAL SHEETS AND STRIPS Filed Dec. 13, 1935 5 Sheets-Sheet 5 I INVENTOR fltmo M) 1 M Patented June 11, 1935 UNITED STATES PATENT OFFICE;

"mz'rnon Arr-mans r: w tacto United Engineering & Foundry Company, Pittsburgh, Pa.. a corporation of Pennsylvania Application December 13, 1933, Serial No. 702,211

42 Claims.

My invention relates to an improved method and apparatus for manufacturing metal sheets and strips, and particularly to an improved method and apparatus for straightening or leveling relatively wide thin material 'or for breakfor imparting a series of bends to sheet metal,

there being a comparatively large number of rolls in each of the series. Substantially the only adjustment for the rolls is a vertical one and in general it has not been customary to provide these working rolls with backing rolls.

Roller levelers of the type described above have been somewhat unsatisfactory for the reason that they have not been suitable for straightening metal of various thicknesses and tages. The horizontal components of the rolling forces are so great that objectionable flexure of the working rolls is produced since the latter are unsupported in this direction.

The provision of spacing rolls between adja-, cent pairs of working rolls would reduce deflection of the latter because of horizontal components of rolling forces, but the size of the backing rolls is limited, and in' order to provide the necessary rigidity of the rolling structure it would be necessary to increase the diameter of the working rolls beyond that suitable for use'in a roller leveler. The diameter of the working rolls must be maintained relatively ,small, as will be appreciated, in order to secure relativelysharp bending of the sheet material.

In accordance with the present invention, I provide an arrangement by means of which the foregoing disadvantages are avoided. The improved arrangement permits the employment of small working rolls and relatively large backing rolls, thus providing suflicient rigidity for very wide material and reducing the deflection-of the working rolls when under rolling pressure. The

.working rolls may operate on close centers for v Y backing rolls-have'beenemploye'd, :ithas usually 'tothati h w rking r0 l1s'- may-varyrthrough {been necessary-,tb,pa g :the metal between all a range -'Of,- I01- example, from g 321 $0511.

. metal and the de lefiof-fistraightening that:has y ti ac Such ratios. I

- such machines-are not sufiiciently. flexible in leveling the material and also for br a their operation to -adapt them-tor sheet 'meta 1 {loosening sc e on sheettor t i eria .of a fairly-wide- .range of thicknessea. :When The'ratio of the diameter of the back n r0118 '30 "of st ils regardlessnotingd ti ofathe' .ratio,of-approximatelylfl 'hasfibeen'dound to be v a been required.

U I are not-possiblewithroller-levelers of ordinary --Whenever working rolls are usedin combina j; (Hf-1.181181 design; becauselifthe working rolls fis-thatinmwhich all ofathe cooperatingqrolls are in alignment .as' in the usual 4-high2mill.

ltio n with backing; rolls, the ideal arrangement In such case. all of "the forces of compression between the several rolls are in alignment with the plane of their axes and there. are no lateral components. Ifthe rolls-are-in vertical align ment, there are no horizontal components of these forces.

However, when a backing roll for each working roll is used in roller levelers it will be appreciated that, if the backing rolls are of sufficiently large diameter, the distances between adjacent pairs of working rolls would be too great to impart the abrupt small bends that are necessary to properly straighten the material being rolled.

If backing rolls of the usual type and size are 4 provided for each pair of working rolls, the latter may be placed sufliciently close together but the arrangement has certain serious disadvanlweresuflfieiently smalltoperform tha -work for which .applicantsworking rolls :.'are---.: designed, space would not permit-the use of backing rolls of such diameter as to fall within thesai-atios.

The working rolls would, insuch case, be insuflioiently supported,-

The large diameter ofthe'backing rolls reduces the angle between the horizontal and the common tangent of the engaging surfaces of the backing rolls and the working rolls in their offset positions, and accordingly'materially reduces the horizontal components of the rolling forces. Also, any given horizontal deflection of the working rolls has a smaller vertical component since, as the diameter of the backing rolls increases, any deflection of the working rolls is more nearlyentirely horizontal.

The roller leveler of the present invention consists of a plurality of main units of small working rolls and large backing rolls which may be operated in substantially any desired relation to impart the desired degree of bending and the number of bending operations that are provided with a relatively large backing roll inorder to insure that the working rolls will-be.

suiliciently rigid for rolling relatively thick material and yet be small enough and placed sufiiciently close together to act eifectively to produce abrupt reverse bends in thin material. The pairs of working rolls in each unit are staggered relatively to each other as are the upper and lower backing rolls for cooperating therewith. r

The backing rolls are relatively adjustable vertically in accordance with the gauge or thickness of the metal to be rolled. The working rolls are adjustable horizontally, whereby they, may assumevarious positions around the circumferences of their respective backing rolls.

This adjustment changes the angles'between the planes of the axes of the respective pairs of working rolls and varies the relative degrees of bending of sheet metal upon entering and leaving the working rolls of each unit.

The details of the roller leveler of my invention will bev described in connection with the accompanying drawings, in which Fig. 1 is a view in side elevation of a roller leveler constructed in accordance with my invention; Fig. 2 is a longitudinal vertical section of the machine of Fig. 1 taken on line 11-11 of Fig.4; Fig. 3 is a view partly in end elevation and partly in transverse section taken on .line III-III of Fig. 1; Fig. 4 is a view in horizontal section taken partially on line IV-IV and partially on line A-B of Fig. 1, the driving mechanism for the working rolls for the several units of the roller leveler machine being shown diagrammatically; Figs. 5, 6 and 7 are diagrammatic views of the working rolls and backing rolls of a main unit in various relative positions and illustrating the corresponding degrees of bending of metal passing therethrough; and Figs. 8 and 9 are diagrammatic views of all of the working rolls of the roller leveler with a strip of metal passing therethrough.

Referring to the drawings, a roller leveler machine constructed in accordance with my invention comprises a housing I consisting of two side frames 2 and 3 that are suitably spaced and connected together by means of transverse beams 4 at the top thereof and by beams at the bottom.

Each of the side frames 2 and 3 is provided at its upper portion with two downwardly projecting members 6 which separate the space between the end portions of the frames into a seriesof three compartments. The lower portion of each of the frames 2 and 3 issimilarly provided with two upwardly projecting members 1 for dividing the lower portion of the frame into. a series of three compartments that are slightly oifset with respect to the compartments in the upper portion of the frame. This arrangement is shown and described by way of example as the compartments may be, if desired, in vertical alignment by suitably proportioning the chucks for the bearings of the rolls.

An upper and a lower compartment that are in approximately vertical alignment constitute, in effect, a housing or larger compartment for an operating unit of the roller leveler machine. The operating units 8. and 3 are similar in'all substantial respects and one of them will be desponding working rolls are offset or out of-vertical alignment. I V

The lower backing roll I3 is supported at its ends in suitable anti-friction bearings l4. Each of the bearings I4 is mounted in a bearing chuck |5 that, by way of example, is of such dimensions as to occupy the width of the corresponding compartment in the frame, and is secured in position by, for example, having on each side thereof a tongue-and-groove connection to the adjacent portions of the frame.

The working rolls i2 of the lower pair are mounted in bearings I6 that are carried at each end of the rolls by a bearing chuck ll. A vertical eye-bolt l3 and a spring I! at the outer end thereof provides a yielding connection between the chucks IS and I! whereby relative movements of these chucks may occur in order to provide adjustment of the positions of the working rolls l2 of the lower pair circumferentially 'of the lower backing roll II.

The upper backing roll I3 is mounted in bearings l4 similar to those previously described in connection with the lower backing roll, and the bearing chucks 2| therefor are each yieldingly secured to the upper portion of the side frames 2 and 3 by means of four eye-bolts 22 and relatively heavy coil springs 23 for permitting vertical movement of the chuck 2| relative to the housing for adjusting the distance between the backing rolls l3 and thereby correspondingly adjusting the distances between the upper and the lower pairs of working rolls |2.

A chuck 24 supports the bearings l8 of the upper working rolls 2. Two eye-bolts 25 and springs 26 yieldingly connect the chuck 24 to the chuck 2| whereby the chuck 24 may be adjusted horizontally for adjusting the positions of the upper working rolls |2 circumferentially of their backing roll IS. The springs 20 maintain the working rolls |2 in engagement with the backing roll |3.

A screw-down mechanism for adjusting the vertical positions of the bearing chucks 2| for the upper backing roll I 3 comprises a handwheel 28 mounted on a horizontal shaft 28 having pinions 30 thereon for rotating beveled gears 3| on the upper ends of screw-threaded rods 32 which extend through the upper portion of the frames and engage the tops of the bearing chucks 2|. Rotation of the screw-threaded shafts 32 in one direction forces the bearing chucks 2| downwardly against the force of the springs 23 while adjustment of the screwthreaded shafts 32 in the opposite direction permits the springs 28 to draw the bearing chucks 2| upwardly with corresponding effects upon the distances between the backing rolls "and the pairs of working rolls l2. These adjustments are necessary in order to provide for rolling sheet metal of different gauges or thicknesses.

The adjustment of the horizontal positions of the pairs of bearing chucks l1 and 24 for the lower and the upper pairs of working rolls respectively are controlled by a mechanism comprising a hand-wheel 34, a horizontal shaft 55, worm gear mechanisms 96, screw-threaded shafts 31 and links 38 actuated thereby and connected to the respective chucks. Rotation of the hand-wheel 84 in'one direction causes the chucks l1 and 24 to be actuated to the left as viewed in Figs. 1, 2 and 4, to cause the respective pairs of working rolls to correspondingly adjust their angular positions with respect to their respective backing rolls. This adjustment also affects the plane of alignment of the axes of each pair of working rolls and the angle between these planes. Rotation of the hand-wheel 34 in the opposite direction effects corresponding adjustments in the opposite direction.

The construction and arrangement of the operating unit 9 is similar in, all essential respects to those described for the unit 8, the horizontal adjustments of the bearing chucks I1 and 24 for the units 9 being made simultaneously with those for the unit 8 by means of links 39 and 48 which connect the corresponding. bearing chucks l1 and 24 of the units 8 and 9. This arrangement is shown by way of example only, as I may, if desired, provide separate means for horizontal adjustment of the units 8 and 9.

backing rolls may be employed, if desired. There are four rolls 42 in the upper series that are carried by vertically movable frames or chucks 43 controlled by a screw-down mechanism identical with that for units 8 and 9. The lower series of three rolls 42, staggered with respect to those of the upper series, is carried .by chucks 44 pivotally supported at 45. The position of the other ends of the chucks 44 is adjusted by means of wedges 48, Figs. 1, 2, 3 and 4, controlled by a hand-wheel 41 having a screwthreaded shaft 48 with a traveling nut 49 thereon connected to the wedges. The latter are connected by a bar 58.

{Referring particularly to Figs. 2 and 4, suitable guides for sheet metal traversing the roller leveler machine comprise horizontal supporting frames 52 of metal plates or wide bars 53 at the outer ends of the machine and horizontal intermediate frames 54 of similar materialbetween the several units. of suitable form for guiding and supporting the metal while it is passing through the machine. At each end of the machine and inclined upwardly at an angle to the guide frames 52 is a frame 55 for guiding the material into the rolls or for permitting variations in the angle of the material in leaving the machine.

Reference may now be had to Fig. 4 in which The frames 52 and 54 are,

are illustrated certain details of the driving mechanism for the respective pairs of working rolls of the several units 8, 9 and 18. Each of the units 8- and 9 is independently driven by a nected to the gear mechanisms 58 and rolls l2.

Since each unit isprovided with its individual driving motor 51, the relative speeds of the working rolls of the several units may be adjusted as desired by suitably controlling the speed of the respective motors 51.

As also shown in Fig. 4, the rolls 42 of unit in are driven by a motor 51, a gear mechanism 58 and shafts 59 having universal couplings 58 and GI, respectively, connectedto the gear mechanism 58 and to certain of the rolls 42. Shafts 59 are connected to the two inner rolls 42 of the upper series, and, as shown in Fig. 1, each of these rolls is geared tothe adjacent outer roll by means of gears 62 and an idler gear 53. In the lower series of rolls, the two on the right, Fig. 1, are directly-driven and the one on the left being geared to the adjacent roll by gears 62 and an idler gear 53. Accordingly, all of the rolls 42 operate at the same speed and in the same direction.

In the operation of the roller leveler machine it may be assumed that sheet metal is to be rolled thereby and that all of the units 8, 9 and 18 are to be in operation to successively roll the metal. The screw-down mechanisms comprising the hand-wheels 28 will be adjusted to suitably space the backing rolls and the working rolls of the several units. The hand-wheel 34 will be adjusted to correspondingly adjust the positions of the working rolls of the units 8 and 9 with respect to each other and with respect to their respective backing rolls. The latter adjustment of the working rolls governs the degree of bending to which the metal is subjected upon entering the working rolls and the degree of bending that is applied thereto when the metal leaves the'unit 8 in the direction of the unit 9 and leaves the latter unit in the direction of the unit II), it being understood that tension is exerted upon the metal between the several units.

When the working rolls l2 are adjusted around the circumferences of the relatively large backing rolls l3, they will be moved toward or away from positions of alignment with the backing rolls in which the horizontal or lateral components .of the rolling forces are substantially zero. The more nearly a working roll approaches such position of alignment, the greater is the portion of the rolling load that is assumed by it. It is therefore highly advantageous that adjustments of the working rolls to exert greater force upon the material also reduces the components which tend to deflect or bend the working rolls.

While the working rolls of the units 8 and 9 may, if.desired,be adjusted to similar or corresponding positions, whereby the amount of work performed by them is substantially equal, it may be preferable to adjust the working rolls of the unit 8 to perform a greater amount of work than is imposed upon the working rolls of the unit 9. Better results are obtained when thedegree of bending is progressively diminished as the metal passes through the machine.

The metal passes through the several units successively and the bending'that is exerted by the staggered sets of working rolls operates to impart a straight flat surface to the sheet metal. By reason of the adjusting mechanisms, the distribution of work between the several units may be varied as desired and suitable adjustments may be made in order that the working rolls may exert suitable bending effects to accomplish the desired results.

Due to the abrupt-small bends imparted to the strip by the working rolls l2, it is possible for the leadingend of the metal to curl down and the trailing end to curl up as they leave such rolls. To prevent this possibility, the larger rolls 42 are provided and by means of the screw-down mechanism therefor and the wedges 46 they can be so adjusted as to deliver the entire strip or sheet in a perfectly flat and leveled condition.

Referring to Figs. 5, 6 and 7, various relative positions of the rolls of an operating unit such as 8 or 9 are diagrammatically showntherein. These views also show the degrees of bending of the sheet metal as it leaves or enters the working rolls in the several positions of the latter with respect to their respective backing rolls.

In Fig. 5, the working rolls are adjusted for substantially equal load upon the members of each pair since their respective lines of centers with the backing rolls are at substantially equal angles with the vertical. However, the material leaves the working rolls at an undesirable angle to the horizontal since it may rub with considerable force on the stationary guides and scratching of the metal may result.

In Fig. 6, both pairs of working rolls have been adjusted to the left as viewed in the drawings, and the result is to cause the right-hand working roll of each pair to assume a greater portion of the rolling load since their lines of centers make smaller angles with the vertical. The angle. of the metal with the horizontal on leaving the working rolls is smaller than that in Fig. 5, because the greater degree of bending now occurs upon entering the rolls.

When the working rolls have been adjusted to the relative positions shown in Fig. '7, the right-hand rolls have assumed a still greater portion of the rolling load and a still greater degree of bending occurs when entering the rolls while that upon leaving the rolls has been diminished to such extent that the metal leaves a the rolls substantially in the plane of the pass line through the machine.

As the working rolls are moved to the right through successive positions of which Figs; 5, 6, and 'l are representative, the right-hand working rolls assume a progressively heavier portion of the rolling load, at the same time the horizontal component of the rolling force becomes less as the forces transmitted to the working rolls by the backing rolls and the metal being rolled are more nearly in alignment.

As a result, the greater the load upon any given working roll, the smaller is the horizontal component of the rolling force and tendency to cause flexure of the working roll is diminisehd. The opposite effects are of course produced upon the working rolls moved into positions away from alignment of the rolling forces, but the increase in the horizontal component of the rolling force carried thereby is oifset by the reduction in the rolling force.

While the adjustments of the relative positions of the pairs of working rolls and their backing rolls have been shown and described as effected by moving the working rolls around the axes of the backing rolls, itwill be understood that substantially similar results may be secured by moving at least one of the backing rolls horizontally to change the horizontal distance therebetween. l

The path of metal through the roller leveler machine is shown diagrammatically in Figs. 8 and 9. It will be noted that in each unit, the bending of the metal as it enters the rolls is greater than upon leaving whereby the metal is approximately straight between units. The latter effect is also insured in part by the control of the driving motors'to exert tension upon the metal between units. In Fig. 8, both of the units 8 and 9 are adjusted for greater degrees of bending than they are in Fig. 9. In the latter view, the unit lflis adjusted for greater initial bending than in Fig. 8.

It may be unnecessary to pass metal through all of the three units of the roller leveler machine, and by means of the construction and arrangement described above I may provide that sheet metal passes, for example, through the unit 8 only, the working rolls of the units 9 and I0 being adjusted to permit the free passage of metal therethrough. The latter units will not be driven under these circumstances and there will be, oi course, a corresponding saving in power.

In case it is desirable to operate two units for rolling sheet metal, for example, the unit I may be idle with its working rolls l2 separated to permit the metal to pass freely therethrough. The units 9 and iii are adjusted for operation for producing the desired results, and the operation is as otherwise described for the operation of the entire machine.

As best shown in Figs. 1, 2 and 3, each of the side frames 2 and 3 consists of an upper portion 65 and a lower portion 66 that are connected'at their respective adjacent ends by means of a projecting tongue 61, which extends into a slot 68 and a wedge 69 which looks these parts together. This arrangement permits the removal of the entire upper half of the machine upon removal of all of the wedges 69.

The upper backing rolls l3 and upper working rolls i2 and the upper series of rolls 4! remain in position in the upper half of the housing. by reason of the connection of their bearing chucks to the frames and to each other. The roll assembly for the upper half of each unit may be-removed by disconnecting the eye-bolts -22, each bearing chuck 2| being provided with a projection or.trunnion 10 for engagement by suitable hoisting mechanism. The chucks I5 for the lower backing rolls i3 are also provided with trunnions 10 for similar purposes.

The sectional construction of the housing: and the connection of the rolls and their bearing supports to the corresponding parts of the main housing provide a simple and convenient arrangement for assembling and disassembling the entire machine or the repair or replacement of any of its working parts.

From the foregoing it will be noted that I have provided a roller leveler machine comprising a series of aligned units for successively rolling sheet metal. The operation of the machine is extremely fiexible since one, two or three units may be employed in accordance with the character of the material that is to be rolled orthe treatment that is necessary for straightening it.

Further flexibility of operation is obtained by the provision of separate means for adjusting the relative positions or the backing rolls of the several units and the provision or means ing or metal upon entering and leaving the working rolls of each unit. By means or this latter arrangement the machine may be conveniently adjusted for exerting a relatively large degree of bending when the metal enters the machine and a relatively small degree of bending when the metal leaves the machine in order that the metal may leave the machine at an angle to the horizontal that varies therefrom as little as possible.

The provision of the diilerent types of units, one type such as units 8 and 9 with small working rolls adapted for heavy duty in reversely bending sheet metal, and the other type for smoothing out curved portions for preventing bowed end portions permits the leveling of metal strip to render it flat throughout its entire length, including parts delivered without tension. The combination of these units secures results that can not be secured by levelers having a single typeoi rolls.

The abrupt reverse bends produced by the small working rolls of the main units efie'ctively loosen or break the scale on strip or sheet material as it is passed through them, and hence renders the machine, or one or more units thereof, particularly suitable for scale breaking, purposes.

The foregoing and other advantages will be apparent to those skilled in the art of construction and operation of roller leveler machines.

I claim:

l. A roller leveler machine comprising a pair of upper working rolls, a pair of lower working rolls in staggered relation thereto, a backing roll for each pair of working rolls, the centers of said backing rolls being out of vertical alignment, and means for adjusting each pair of working rolls around the corresponding backing roll. J

2. A roller leveler machine comprising a pairthe relative degree of bending of material upon I entering and upon leaving the working rolls.

4. A roller leveler machine comprising a pair or upper working rolls, a pair or lower working rolls in staggered relation thereto, a backing roll for each pair of working rolls, the axe's'or said backing rolls being out of vertical alignment, and means for varying the angle of sheet metal with respect to the horizontal upon entering and upon leaving said working rolls, said means comprising devices for simultaneously ad- Justin; the pairs of working rolls circurnterentially of their respective backing rolls.

5. A roller leveler machine comprising a pair of upper working rolls, a pair oi. lower working rolls, a backing roll for each pair of working rolls, means for adjusting the relative positions of said backing rolls vertically, and horizontally movable means for adjusting the positions of said working rolls relative to their respective backing rolls.

. 6. A roller leveler machine comprising a housmg, an upper and a lower pair or working rolls; a backing roll for each pair or working rolls, a vertically adjustable bearing support for each of the ends of the upper backing roll, and a horizontally adjustable bearing support for the ends of each pair of working rolls.

'7. A roller leveler machine comprising a housing, an upper and'a lower pair of working rolls, a backing roll for each pair of working rolls,

. a vertically adjustable bearing support for each of the ends of the upper backing roll, a horizontally adjustable bearing support for the ends of each pair of working rolls, and means for connecting each bearing support for a pair of working rolls to an adjacent bearingsupport for the backing roll cooperating with said pair of working rolls. I

8. rollerleveler machine comprising a housing, an upper and a lower pair of working rolls, a backing roll for each pair of working rolls, a vertically adjustable bearing support for, each of the ends of the upper backing roll, a horizontally adjustable bearing support for the ends of each pair of working rolls, means for yieldingly connecting the bearing support for the upper backing roll to said housing to yieldingly hold said supports and said backing roll to their uppermost positions, .and means for yieldingly connecting each bearing supp rt for a pair of working rolls to a bearing support for. the corresponding backing roll for permittingrelative movement therebetween.

9. A roller leveler machine comprising a housing, an upper and a lower pair of working rolls, a backing roll for each pair of working rolls, a vertically adjustable bearing support for each of the ends of the upper backing roll, a horizontally adjustable bearing support for the ends of each pair of working rolls, means comprising springs for connecting the bearing supports for the upper backing roll to said housing to yieldingly hold these supports and said upper backing roll to their uppermost positions, a screw-down mechanism for adjusting the vertical positions of the upper backing roll bearing supports against the force of said springs, means comprising springs for connecting each of the bearing supports for the ends of each pair of working rolls to a bearing support for the corresponding backing roll for yieldingly retaining them in engagement but permitting relative ovement therebetween, and means for moving the working roll bearing supports horizonly rolling sheet metal passing therethrough, each of said units comprising two pairs of cooperating working rolls, mans common to the rolls of each pair 01' said working rolls comprising the sole means for preventing them from being deflected between their ends by the rolling forces encountered, and means for independently adjusting the working rolls of one. or said units with respect to those of another unit in the series for varying the relative eflects of said units upon said sheet metal.

11. A roller leveler machine comprising a plurality of aligned operating units for successively rolling sheet metal passing therethrough, each oi said units comprising two pairs of cooperating working rolls, means common to the rolls of each pair of .said working rolls comprising the sole means for preventing them from being deflected between their ends by the rolling forces encountered, and means for independently adjusting the working rolls of each of two of said units of the series for varying their relative effects upon said sheet metal.

12. A roller leveler machine comprising a plurality of aligned operating units for successively rolling sheet metal passing therethrough, each of said units comprising two pairs of cooperating working rolls and a backing roll for each pair of-working rolls, and means for independently adjusting the backing rolls of one of two adjacent units for varying the relative effects of said adjacent units upon said sheet metal.

13. A roller leveler machine comprising a plurality of operating units, each unit comprising a plurality of working rolls and backing rolls therefor, means for independently driving the working rolls of the several units, whereby'one or more units may be operated at any given time, and means for separately adjusting the relative positions of the backing rolls of the several units.

14. A roller leveler machine comprising a plurality of operating units, each unit comprising aplurality of working rolls arranged. in staggered relation, and means for independently driving the working rolls of the several units to tend to operate the working rolls of the second and third units progressively faster than those of the first unit to thereby exert tension upon sheet metal \traversing said machine. 15. A roller leveler machine comprising a plurality of operating units, each unit comprising a plurality of working rolls arranged in staggered relation, and means for driving the working rolls of the several units simultaneously but independently of each other to exert tension between said units on sheet metal traversing said machine.

16. A roller leveler machine comprising a series of aligned operating units for successively rolling sheet metal passing therethrough, each of said units comprising a plurality of upper and lower working rolls arranged in staggered relation, separate driving means for the working rolls of the respective units, and means for ad justing the working rolls of one of said units independently of the other units to vary the effect of said one unit upon said sheet metal.

17. A roller leveler machine comprising a series ,of aligned operating-units for successively rolling sheet metal passing therethrough, each of said units comprising a plurality of upper and lower working rolls arranged in staggered relation, separate driving means for the working rolls of the respective units, and means for adjusting the working rolls of one of two adjacent units to vary the relative eitects or said adjacent units upon said sheet metal.

18. A roller leveler machine comprising three operating units each including a plurality of working rolls and backing rolls therefor. means for adjusting the positions of certain of the backing rolls. means for adjusting the relative positions of the working rolls of one of said units independently or the other units, and means for adjusting the relative positions of theworking rolls or the remaining two units simultaneously.

19. A roller leveler machine comprising a housinghaving a series oi compartments therein, a-series of aligned operating units mounted in the respective compartments, each of said units comprising a series of, working rolls, backing rolls therefor, means connected to said housing for adjusting the relative positions of the backing rolls of each unit, and means connected to said housing for adjusting the relative positions or said working rolls of each unit.

20. A roller leveler machine comprising a housing having a series or compartments therein. a series of aligned operating units mounted in the respective compartments, each of said units comprising a series of working rolls, backing rolls therefor, means connected to said housing for adjusting the relative positions of the backing rolls of each unit, and means connected to said housing for adjusting the posiv tions of the working rolls of each to their respective backing rolls.

21. A roller leveler machine comprising a housing having a series of compartments therein, a series of aligned operating units mounted in the respective compartments, each of said units comprising a series of working rolls, backing rolls therefor, means connected to said housing for independently adjusting the relative positions of the backing rolls of the several units, and means connected to said housing for adjusting the positions or the working rolls of certain of said units with respect to the working rolls of another unit.

22. A roller leveler machine comprising two pairs of cooperating working rolls, a backing roll for each pair of working rolls, and means for adjusting the relative positions oi a pair of working rolls and their backing rolls to vary the degree of. bending of sheet metal upon entering and leaving said working rolls, such adjustment reducing the horizontal component of the rolling force on any working roll as the rolling force thereon is increased.

23. Apparatus for reversely bending sheet metal comprising two pairs of cooperating working rolls, a backing roll for each pair 01' working rolls, and means for adjusting the relative positions of a pair of working rolls-and their backing roll to vary the degree 01 bending of sheet metal upon} entering and leaving said working rolls, such adjustment causing the horizontal component of the rolling force on each working roll to vary inversely with the rolling force thereon. I

24. Apparatus for reversely bending sheet metal comprising an upper and a lower pair of cooperating working rolls, a backing roll for each pair of working rolls, and means for adjusting each pair of working rolls around the axis of the adjacent backing roll, such adjustment reducing the horizontal component of the rolling pressure tending to produce flexure of unit relative 01 working rolls around the axis oi. the adja centbacking roll, such adjustment causing the horizontal component of the rolling pressure on each working roll to increase or decrease according as the rolling pressure on such working roll is decreased or increased, respectively.

26. A roller leveler machine comprising a series of operating units each of which comprises two pairs of cooperating working rolls, a backing roll for each pair of working rolls, and means for varying the relative angular positions of said working rolls and their corresponding backing rolls while maintaining engagement therebetween.

27. Apparatus for reversely bending sheet metal comprising a plurality of operating units each of which comprises two pairs of cooperating working rolls, a backing roll for each pair of working rolls, and means for varying the relative horizontal and vertical positions of each of said backing rolls and its corresponding pair of working rolls.

28. Apparatus for reversely bending sheet metal comprising a pair of upper working rolls, a pair of lower working rolls, a backing roll for each pair of working rolls comprising the sole means for preventing said rolls from being deflected and means for circumferentially adjusting said working rolls about the backing roll.

29. Apparatus for reversely bending sheet metal comprising a plurality of rolls for engaging metal passing therebetween, the rolls for engaging one side of said metal comprising a pair of working rolls of relatively small diameter and a backing roll therefor comprising the sole means for preventing deflection of the working rolls, said backing roll being suificiently larger than the working rolls and the working rolls mounted sufficiently close together against the backing roll to prevent objectionable deflection of the working rolls by the rolling forces encountered.

30. Apparatus for reversely bending sheet metal comprising upper and lower pairs of cooperating working rolls of relatively small diameter arranged in staggered relation, and a backing roll for each pair of working rolls, said backing roll comprising the sole means for preventing deflection of the associated working rolls and being sufiiciently larger than the working rolls and the working rolls mounted sufficiently close together thereagainst to prevent objectionable deflection of the working rolls by the rolling forces encountered.

31. A roller leveler machine comprising a series of conjointly operative units for successively leveling sheet metal, certain of said units comprising relatively small working rolls for producing abrupt bends in said metal strip, relatively large backing rolls for said working rolls, and the last of said units in the series comprising two series of working rolls of larger diameter than those in the preceding units in the series for producing relatively slight bends in the metal strip.

32. Apparatus for reversely bending sheet metal' comprising upper and lower pairs of cooperating working rolls and backing rolls therefor which constitute the sole means engaging said rolls between their ends for preventing them from being deflected by the rolling stresses encountered, thediameter of said backing rolls and that of said working rolls having a ratio of approximately 4: 1.

33. Apparatus for reversely bending sheet metalcomprising upper and lower pairs of cooperating working rolls and backing rolls therefor which constitute the sole means engaging.-

said rolls between their ends for preventing them from being deflected by the rolling stresses encountered, the diameter of said backing rolls and that of said working rolls having a ratio of not less than 3:1.

34. Roller leveler apparatus comprising a series of working rolls for producing relatively sharp bends for eifectively leveling sheet metal, and a series oi. working rolls for producing relatively light bends i'or straightening'curved end portionsoi said sheet metal.

35. Roller leveler apparatus comprising a series of relatively small working rolls for producing relatively. sharp bends for effectively leveling sheet metal, and a series of relatively large-working rolls for producing relatively light bends for straightening curved end portions of said sheet metal.

36. In a metal working machine, a plurality of groups oi. iour relatively small working rolls mounted in pairs one above the other, and a backing roll for each of said pairs of working rolls which comprises the sole means for preventing deflection of the working rolls, said backing roll being sufficiently larger than the working rolls and the working rolls mounted sufficiently close together against it to prevent objectionable deflection of the working rolls by the rolling forces encountered.

37. In a metal working machine the combination'of a pair of relatively small working rolls, a relatively large backing roll therefor comprising a rolling unit andsaid backing roll comprising the sole means for preventing flexing of both of said working rolls in any direction when subjected to rolling stresses, the working rolls being mounted sufiiciently close together to permit the backing rolls to function in the manner set forth.

38. The method of removing scale from, leveling and straightening metal strip consisting in passing it continuously through a series of wave-shaped roll passes in which it is reversely deflected at a relatively sharp angle, tensioning it while it is being so worked and then passing it without appreciable tension through a final wave-shaped roll pass in which the deflection eflected is of a diminishing character as compared to that of the first-mentioned passes.

39. The method of removing scale from, leveling and straightening metal strip consisting in passing it continuously through a series of waveshaped roll passes in which it is reversely deilected at a relatively sharp angle but to a diminishing extent in each succeeding pass, subjecting it to tension between said passes and then passing it without appreciable tension through a final pass of the same general character in which it is subjected to a deflection of a lesser degree of curvature.

40. The method of removing scale from, leveling and straightening strip metal consisting of progressively bending it reversely at spaced intervals in a wave-like manner about rolls having a relatively small radius of curvature in each direction, 'tens'ioning it while so bending it and finally, reversely bending it progressively about a somewhat larger radius of curvature in each direction without appreciable tension.

41. The method'of treating metal strip which comprises passing it through a series of waveshaped roll passes in certain of which it is bent reversely about rolls having a relatively small radius of curvature and then finally through a pass in which it is reversely bent about rolls having a somewhat large radius of curvature.

42. The method 01 treating metal strip which consists in continuously passing it through a series of relatively small rolls arranged-in staggered relation to loosen the scale, remove bulges. kinks, etc., and then passing it through a similar arrangement of larger rolls to flatten it.

FLORENCE C. BIGGERT, JR.

cannricam or commotion Pmm No. 2,004,596. 1m 11. 192.5.-

FLORENCE c. BIGGERT; m.

It is hereby certified that error appears in the 'printed specification of the above numbered patent requiring correction as follows: Page 7, second column, line 74, claim 40, strike out the words "rolls having"; and that the said Letters Patent should be read with this correction therein that the same may "conformanc of the case in the Patent Office.

Signed and sealed this l 6th day of July, A. D. 1935.

Leslie Frazer (Seal) Acting Commissioner of Patents. 

